Springs of this general type are not new per se. West German Utility Pat. No. 77-03,393 shows a typical prior art type of design. In accordance with the design shown in this West German Utility Model Pat., a tubular vibration damper is provided with a piston rod which moves in a linear manner inside it. A helical spring is mounted coaxially on the tube with a small amount of radial clearance. The spring is braced at one end against the stop on the tube and at the other end against a stop on the piston rod. In the tension state, nearly all of the turns of the helical spring are on the tube. The spring is generally cylindrical since all of the turns have the same diameter. It has been found that the individual turns, particularly in the middle section of the spring move out of axial alignment when the spring is tensioned and touch the tube of the vibration damper. This is attributable to unavoidable tolerances during mass production of these springs and diameter variations or structural differences in the starting raw material for making the springs. Due to the linear strokes which occur at various vibration frequencies during operation, there is constant frictional contact between the spring and the tube which generates noise and causes wear. One solution to this problem would be to increase the diameter of the turns and thus create more space between the vibration damper and the spring. However, tension rollers are usually installed together with other assemblies of the belt drive in automobile vehicles in the space between the engine and radiator. It is noted that this space is already quite cramped and that in general in this region a pre-established structural volume is critical and cannot be exceeded.